Cerastium arvense |
Cerastium axillare |
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céraiste des champs, field chickweed, field mouse-ear chickweed, field or prairie mouse-ear chickweed, meadow chickweed, starry cerastium |
Trans Pecos mouse-ear chickweed, trans-Pecos chickweed |
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Habit | Plants perennial, clumped and taprooted, or mat-forming and long-creeping rhizomatous. | Plants annual, viscid. | ||||
Stems | flowering shoots often decumbent proximally, 5–20(–30) cm, glandular-pubescent distally, pilose-subglabrous, deflexed or spreading proximally; non-flowering shoots present; small tufts of leaves present in axils of proximal leaves. |
usually erect, simple or several-branched, from branched caudex, rarely bushy, 6–40 cm, glandular-pilose, hairs in mid-stem region equaling or longer than stem diam.; small axillary tufts of leaves absent Leaves sessile; blade 7–25 × 1–6 mm; basal rosette absent or poorly developed and withering when young; proximal with blade oblanceolate to spatulate; distal with blade linear-lanceolate or lanceolate to narrowly elliptic, apex usually acute, rarely obtuse, glandular-pilose. |
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Leaves | not marcescent, sessile, ± spatulate proximally; blade linear-lanceolate to lanceolate or narrowly oblong, 4–30 × 0.5–6 mm, apex acute, rarely obtuse, subglabrous to softly pubescent, sometimes glandular. |
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Inflorescences | lax, 1–20-flowered cymes, pubescence short, glandular; bracts lanceolate, margins narrow, scarious, glandular-pubescent. |
diffuse, elongate, usually with single dichotomy at or below mid stem, 3–18-flowered cymes, glandular-pubescent, flowers widely and racemosely spaced in axils of paired bracts along each branch; bracts herbaceous, lanceolate, glandular-pubescent. |
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Pedicels | curved just below calyx, 5–30 mm, 1–6 times as long as sepals, glandular-pubescent. |
sharply curved just below capsule, 2–10(–15) mm, shorter than to 2 times as long as capsule, with dense, patent, glandular pubescence. |
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Flowers | sepals narrowly lanceolate to lance-elliptic, 3.5–7 mm, margins narrow, softly pubescent; petals obovate, 7.5–12.5 mm, ca. 2 times as long as sepals, apex 2-fid; stamens 10; anthers 0.8–1.1 mm; styles 5. |
sepals lanceolate, 3–5 mm, apex acute, glandular-hispid, hairs not extending beyond sepal tips, inner sepals with broad margins, outer sepals with very narrow margins; petals oblanceolate, 2–3 mm, shorter than sepals, apex 2-fid ca. 1/4 of length; stamens 5; styles 5. |
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Capsules | cylindric, curved, 7.5–11.5 × 2.5–4 mm, (1–)1.5–2 times as long as sepals; teeth 10, erect, margins convolute. |
narrowly cylindric, curved, 7–8.5 mm, ca. 2 times as long as sepals; teeth 10, erect, margins convolute. |
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Seeds | brown, 0.6–1.2 mm diam., tuberculate; testa not inflated. |
light brown, 0.4–0.7 mm diam., tuberculate; testa not inflated. |
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2n | = 36, 72, (108, Europe). |
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Cerastium arvense |
Cerastium axillare |
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Phenology | Flowering summer. | |||||
Habitat | Rocky canyons, woodland and mountain slopes | |||||
Elevation | 1300-2800 m (4300-9200 ft) | |||||
Distribution |
AK; AZ; CA; CO; CT; IA; ID; IN; MA; MD; ME; MI; MN; MO; MT; ND; NE; NH; NJ; NM; NV; NY; OH; OR; PA; SD; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NF; NS; NT; NU; ON; PE; QC; SK; YT; Worldwide
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NM; TX; Mexico |
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Discussion | Subspecies 2+ (2 in the flora). The infraspecific taxonomy of Cerastium arvense is subject to many different interpretations. While many subspecies have been recognized, the “actual” number is uncertain because of worldwide distribution, wide range of variation, and conflicting taxonomies. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Cerastium axillare is similar to C. brachypodum in its short pedicels, but it is more viscid-pubescent, with a much more diffuse habit and solitary flowers widely spaced along the elongate, racemelike primary branches of the inflorescence. In addition, the leaves are usually acute, whereas in C. brachypodum they are usually obtuse. Cerastium axillare is confined in the United States to the trans-Pecos mountains of Texas and New Mexico. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 5, p. 79. | FNA vol. 5, p. 81. | ||||
Parent taxa | Caryophyllaceae > subfam. Alsinoideae > Cerastium | Caryophyllaceae > subfam. Alsinoideae > Cerastium | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Name authority | Linnaeus: Sp. Pl. 1: 438. (1753) | Correll: Brittonia 18: 308. (1967) | ||||
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